DESCRIPTION: The goal of this core is straightforward, and in light of the large number of mouse strains involved in this proposal, a Genetic Models Core is well warranted to facilitate progress of the projects. The function of the Core includes: 1) Breeding and maintaining a minimum of 12 different strains of transgenic and mutant mice (FEN-1 knockout, FEN-1 inducible, HD61, HD62, DM-PK, SupFG1 tg, DNA-PK, PMS2, MLH1, Tta tg, and a minimum of 2 strains of long-repeat transgenic mice). 2) Genotyping all the mice generated by PCR or Southern. 3) Coordinating with PIs and generating mice of appropriate genotype at appropriate time for experimental needs. This includes time mating for generating mutant fetuses. 4) Monitoring the aging colony and notifying the PIs when health problems with mice arise. 5) Administering tetracycline to FEN-1 inducible mice. 6) Keeping all the records of animal breeding.